Possible urine test after1 joint in 2 years! Need advice

About 3 weeks ago I smoked 1 joint at a party. This was after 2 years of abstinence. I am 5'2", and weigh 235. I have not smoked anything since. I just found out that I may be subjected to a urine test by social services because of wrong doing by my ex-husband. They feel that if he has been abusing drugs then I am too. I am worried to death that this 1 slip on my part is going to cause me to lose my son. I have read about diluting and the time THC stays in your system and am curious as to any advice that others could give me. I drink over a gallon of tea a day and urinate frequently as part of my natural routine. Any advice would be great.

Pick up a THC test kit and test yourself to see where you actually stand. When testing yourself, be sure to use the first urination of the day. If your test kit results are non-negative, you have only two viable options:

- Dilution.....Read up on the steps (disregard the 'aspirin' step) outlined in this thread: http://boards.cannabis.com/drug-test...uidelines.html

- Substitution..... Tips on pulling off a successful sub can be found on this thread: http://boards.cannabis.com/drug-test...uidelines.html